My 2c
I use superpro in all my cars and I sell them for the following reasons
Theyre made in australia
Theyre oven cured, not just air cured like noltec etc
They last the longest out of any that I have tried
They are willing to adapt and make new bushes and change bushes (rack mount bushes - changed a few durometers for me as well)
Most comprehensive list
I have had no returns and no issues since I started using them about 8 years ago.
The new whiteline black bushes are no chinese, they used to use superpro when whiteline was aust made...